Mitchell Pearce breaks down after pectoral injury nightmare

Mitchell Pearce has torn his pectoral muscle and will miss the entire 2018 State of Origin series.

The star halfback could miss the entire 2018 season, Knights coach Nathan Brown admitted after his team's gutsy comeback win over the Tigers in Tamworth on Saturday night.

Pearce was forced from the field with five minutes to play and did not return to the field.

Brown said the injury is "long term" but stressed the torn pec is only the initial injury diagnosis.

Pearce held his head in his hands as a trainer helped him from the field.

He sat on the bench, clearly upset, for the final dramatic moments of the match.

The Knights confirmed Pearce's tears were the result of a pectoral tear which will likely see him miss at least 12 weeks.

Mitchell Pearce leaves the field. Photo / Getty Images

"It's not great," Brown said.

"He is disappointed. Mitch loves playing. Game day is his favourite day of the week. They are the types of players you want in your club. Whatever the result is he will still contribute while he is not playing."

Pearce's injury overshadowed a dramatic, momentous win for the Knights.

A 79th-minute try to Shaun Kenny-Dowall gave Newcastle a stunning 22-20 comeback win over the Wests Tigers to move into the NRL top eight.

The Tigers were leading by two points late on Saturday when Jamie Buhrer, with Mitchell Pearce off the field with concussion, kicked for Kenny-Dowall in the corner to steal a miracle victory.

It appeared the Knights had wasted a 10-point halftime lead when the Tigers came out of the sheds and scored three tries in five minutes to surge to an 18-10 lead.

But a last-ditch play from Buhrer gave the Knights their fourth win of the season, and also ended the Tigers' winning streak at three in dramatic circumstances.

Brown said he expects Connor Watson to return for their clash with Manly at Brookvale Oval on Friday to partner Jack Cogger in the halves.

"It's not a great thing when anyone loses their halfback and one of their best players," Brown said.

"We'd like to think experience with some of our younger halves, our squad is stronger. We should be able to overcome these things."

Broncos legend Justin Hodges told Fox League the loss of Pearce for potentially the entire year will be "heartbreaking" for his teammates.

Knights winger Ken Sio was an unlikely hero in front of the 10,082 crowd in Tamworth, finishing with his first-career hat-trick to save the goalkicking blemishes of star fullback Kalyn Ponga.

Ponga's wayward kicking appeared to have cost them the two points after converting just one of five attempts before Kenny-Dowall's heroics.

Mitchell Pearce scored a try before he left the field later with injury. Photo / Getty Images

The win lifted Newcastle back into the top eight on four wins. The Tigers missed an opportunity to join St George Illawarra and the Warriors at the top of the table and remained in fourth spot.

The Knights had the upper hand at halftime after a solid opening 40 minutes, beginning with Ponga's sublime cutout for Sio to draw first blood in the 21st minute.

Knights forward Lachlan Fitzgibbon fumbled an opportunity not long after, but concussion tests for Jacob Liddle and Benji Marshall paved the way for more shots at the Tigers' line.

And Pearce didn't need a second invitation, slicing through in the 34th minute to give the Knights a 10-point lead at the break.

Marshall's return immediately paid dividends for the hosts, with the reborn playmaker bombing for Kevin Naiqama and chipping for Corey Thompson to give his team the advantage.

But the Knights pulled one back with Fitzgibbon's cutout for Sio, before finding a way to cross the line late and take another step in their improved season.

— with AAP

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